I do mean KD1JV. However, I don't think Steve ever wrote anything up. If I
recall, he used the TRF4900 which is a "transmitter" - basically a DDS with
an amplifier. The 4400 looked a little more interesting to me, same thing,
lower frequency. I've been meaning to do something similar for a while now.
I had assumed that you needed to operate these parts somewhere near their
spec frequency, 900 MHz for the 4900, 450 for the 4400. Steve went right
down to 6 meters for his first whack and had no problems.
What is interesting about these is that they are reasonably priced, and the
frequency steps are small enough that you are in the neighborhood of a Hz or
two after dividing them down to HF, reasonable for a CW rig. They are also
easily obtained.
TI also has a series of synthesizer chips, the 2050 and 2052 that seems to
be a bit more flexible, but maybe more complicated. All these parts are
under five bucks quantity one.
I have to admit, after getting over my shyness over asking AD for samples,
the AD parts look a lot more appealing. But I have a few of these TI chips,
and I finally got a prototyping board that will work with them, now if I can
just get the time to play with them...
...
"PaoloC" wrote in message
...
xpyttl wrote:
Do you have any reference to Weber's project? I would love to have a
look at that circuit!
BTW, do you mean SteveN Weber, KD1JV?
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